The spine is subject to various pathologies that compromise its load bearing and support capabilities. Such pathologies of the spine include, for example, degenerative diseases, the effects of tumors and, of course, fractures and dislocations attributable to physical trauma. In the treatment of diseases, malformations or injuries affecting spinal motion segments (which include two or more adjacent vertebrae and the disc tissue or disc space therebetween), and especially those affecting disc tissue, it has long been known to remove some or all of a degenerated, ruptured or otherwise failing disc. It is also known that artificial discs, fusion implants, or other interbody devices can be placed into the disc space after disc material removal. External stabilization of spinal segments other external stabilization devices have been helpful in the stabilization and fixation of a spinal motion segment, in correcting abnormal curvatures and alignments of the spinal column, and for treatment of other conditions.
While external rod systems have been employed along the vertebrae, the geometric and dimensional features of these rod systems and patient anatomy constrain the surgeon during surgery and prevent optimal placement and attachment along the spinal column. For example, elongated, one-piece rods can be difficult to maneuver into position along the spinal column, and also provide the surgeon with only limited options in sizing and selection of the rod system to be placed during surgery.
SUMMARY
The present invention relates to embodiments for a spinal construct system having a first spinal fixation element attachable to a second spinal fixation element in end-to-end fashion with a coupling mechanism that axially and torsionally constrains the first and second rods to one another. In one embodiment the spinal constructs system includes a spinal fixation plate attachable to fixture element in end-to-end fashion with a coupling mechanism that axially and torsionally constrains the first and second elements to one another. In one form, the end-to-end attachment arrangement is aligned along a common axis of the elements. In another form, the axes of the elements are offset laterally relative to one another.